We are proposing a telephone follow-up study of the psychiatric status of approximately 1300 male and female juvenile twin pairs as thy make the transition from late adolescence to early adulthood. Extensive psychiatric information is already available on these twins and their parents, having participated in the Virginia Twin Study of Adolescent Behavioral Development (VTSABD) a three wave, longitudinal study designed to investigate the influence of genetic and environmental factors on the development of childhood and adolescent psychopathology in the ages 8 through 16. The extensive array of psychopathological, environmental, and developmental data on this large epidemiologic twin sample represents and unprecedented opportunity to understand how hereditary and environmental factors in childhood may culminate in psychiatric problems in young adulthood. The availability of genetically informative data within a longitudinal framework from early childhood to young adulthood will enable us to address some of the most important questions about the various genetic and environmental pathways to Major Depression, Generalized Anxiety disorders, social, Situational, and Simple Phobias, Antisocial Personality Disorder, Alcoholism, Drug use, and Eating Disorder. These include: what salient risk factors, both genetic and environmental, contribute to an individuals; liability to psychiatric disorder in early adulthood? What are the mechanisms that can account for the continuity/discontinuity between juvenile and adult psychiatric outcomes? To what extent can behavioral continuity be attributable to an individuals selecting or creating environments that potentiate their genetic liability to certain behaviors? And finally, are the genetic and/or environmental factors that contribute to behavior in adolescence that same as those that influence psychiatric disorders later on in adulthood? We propose to utilize an extensive array of methodological strategies to both twin and family data to address these most fundamental questions concerning the pathways to adult psychiatric morbidity.